Universal hydraulic suspended pipe wrench

FIELD: drilling oil and gas wells; devices for screwing and unscrewing casing pipes.

SUBSTANCE: proposed wrench includes power unit in form of electric motor, hydraulic pump with constant power regulator and tank filled with working medium. Actuating mechanism includes hydraulic motor, gearbox, rotor with pipe grip, movable doors with locks and hydraulic distributor. Constant power regulator is provided with delay unit in form of prestressed spring. Axial-flow piston-type pump is used as hydraulic pump; it is provided with movable unit with spring and its pistons are arranged in inclined position. Constant power regulator inlet is connected with main hydraulic line and its outlet is connected with cylindrical movable unit of hydraulic pump. Constant power regulator may be switched-off by delay unit. Regulator is switched on when output power of power unit and output of hydraulic pump reach the magnitudes preset by the following formulae: where N, are respectively output power and normal output power of power unit; Q are respectively output and nominal output of hydraulic pump; P are respectively pressure and nominal pressure of working medium in hydraulic line, k is proportionality factor equal to 1.

EFFECT: enhanced efficiency, reduced wear; increased universality factor.

4 dwg

 

The invention relates to a device for screwing and unscrewing the casing OCTG pipes in the process tripping when drilling oil and gas wells.

Well designed for industrial operation, it is necessary to secure the casing. Installation of casing pipes in a single structure using threaded connections because of their impressive size, and a considerable weight is hard work and cannot be performed without the use of special equipment, the so-called pipe wrench.

When creating a universal pipe wrench, it is necessary to solve complex technical problems, including such as:

to ensure reliable operation of the key when the installation of pipes with different mass and dimensional characteristics without a substantial readjustment of the equipment;

the exception is the extreme modes of operation of the equipment, the process of minimizing potential emergency situations working with key;

optimization of operating modes of the equipment by the criterion of minimum weight, energy consumption, etc.;

providing the specified resource characteristics.

In the simplest case, the installation of casing pipes is carried out on the following technology. The pipe in the well and extends partially above the surface of the soil, completely restricted to d is igenii. The joined pipe supported on weight at one end, for example, using a crane or other similar device. Next is placing the assembled pipe in a vertical position and combination of its longitudinal axis with the longitudinal axis of the stationary pipe. Then mounted the tube rotates around the axis up until the threaded part of the pipe will not be in contact completely. To perform the last of these operations, you use a pipe wrench, when he should be suspended.

To achieve reliable operation of the key when the installation of pipes with different mass and dimensional characteristics it is necessary to solve the problem associated with providing health equipment in a wide range of change of the moment of resistance of the assembled tube. With this purpose, use of corrective devices that are included in the work under certain modes of operation of the key. Corrective devices change the output characteristics or the so-called target function key so that the equipment became operational in the entire variation range of the mounted pipe (automatic control Theory edited Aventura. M.: Higher school, 1976).

As the output characteristics for the comparative analysis of pipe wrenches, various devices useful is brasno to use according to respectively the output power of the power unit and the performance of the hydraulic pump from the pressure of the working fluid in the supply lines (hereinafter output characteristics of the key).

Known hydraulic suspension pipe wrench (user Manual. The firm Weatherfbrd, Texas, USA, 1993). Known hydraulic suspension key consists of a power unit 1, the actuator 2, the measuring devices 3 and hydraulic circuits with necessary fittings 4.

The power unit 1 includes an electric motor 5 with the coupling 6, the hydraulic pump low pressure 7, the check valve 8, the hydraulic pump high pressure tank 9 and 10 with the working fluid (oil). The hydraulic pump low pressure 7 plays the role of a corrective device on and off automatically from when the preset pressure of the working fluid in the supply lines. Pump high pressure 8 operates continuously.

The actuator 2 includes the hydraulic motor 10, the transmission 11 with satellites 12, rotating open rotor 13 with the pipe clamp 14, the movable sash 15, case 16, the lock 17, the valve 18, the valve 19 (see Fig 1, 2, prototype)

In the prototype to ensure reliability during installation of pipes with different mass and dimensional characteristics used scheme parallel connection of the hydraulic pump low pressure hydraulic pump 7 and the high pressure 9. Through the use of a corrective device mode key is divided into two sections: the first is chastek - the key works with correcting device; the second section is the key works without corrective devices.

The output characteristics of the prototype graphically shown in figure 2, where Q=f(p) - curve 1, N=f(p) - curve 2; QNomNNompNomaccordingly nominal capacity, power output and pressure of the hydraulic pump low pressure; QNomNNomaccordingly nominal capacity, power output and pressure of the hydraulic pump high pressure.

Since the motor has almost a constant speed regardless of load, the throughput (the amount of working fluid pumped by the pump per unit time) of each hydraulic pump has a constant value, with an increase in pressure in the supply lines required output power of the power unit increases.

The peculiarity of the output characteristics of the prototype is that on the border areas of work of key defined by the cut-off adjustment device (hydraulic pump low pressure), abruptly reduced performance and power output, and with further increase of load, therefore, the pressure of the working fluid, the performance remains unchanged, and the required output power increases linearly.

Insufficient the AMI of the prototype are: the relatively low efficiency of key a high degree of wear of the moving parts of the actuator, and a relatively low coefficient of versatility.

The low efficiency of the prototype is that the motor normally operates in a mode that differs significantly from the nominal, and hence low efficiency. In addition, the pump low pressure on the second site (see figure 2 prototype) does useless work, pumping the working fluid through the check valve 8 into the tank 10 (Wpintee. Fundamentals of electric drive. M: State energy publishing house, 1963). This was illustrated by the respective output characteristics of the prototype N=f(p) (figure 2, curve 2).

A high degree of wear of the moving parts of the actuator associated with the presence of the mode key when changes abruptly its performance (see figure 2). This leads to the fact that the speed of rotation of the elements of the actuator decreases sharply, and its details are experiencing shock, leading to an increase in the extent of their deterioration. This effect is also illustrated by the output characteristics of the prototype Q=f(p) (figure 2, curve 1).

The invention aims: increase efficiency, reduce wear on the moving elements of the Executive mechanism is ZMA, as well as the increase of the coefficient of the universality of the key.

The problem is solved in that in the universal hydraulic suspension pipe wrench, comprising a power unit containing a drive motor connected therewith by coupling the hydraulic pump with a device for the correction performance of the hydraulic pump and the output power of the power unit and tank with a working body, formed by the layout of its elements in a single housing, the actuator including a hydraulic motor, gearbox, disclosed a rotating rotor with a pipe clamp and a movable sash lock, valve, safety valves, measuring devices, the respective hydraulic circuits with the main hydrological and necessary valves, a device for correction performance of the hydraulic pump and the output power of the power unit made in the form of the constant power regulator with delay device, for example, in the form of pre-compressed springs, as the water pump used pump axial piston type with a cylindrical movable unit including a spring, and a sloped position of the piston, providing the ability to change the performance of the pump by changing the angle of inclination of the pistons relative to the longitudinal axis of the actuator in the form of e is eradicates, at the entrance to the constant power regulator connected to the main hydrological, and the output from the cylindrical movable block of the hydraulic pump and the constant power regulator configured to include a delay device, for example, in the form of a pre-compressed spring, when reaching the output power of the power unit and the performance of the pump, determining the mode of operation of key values specified by the formula

where N, NMr.- accordingly, the output power nominal output power of the power unit;

Q, QMr.accordingly, the productivity, the nominal capacity of the hydraulic pump;

p, pMr.- pressure, nominal pressure working fluid in the supply lines, p≥pMr.;

k - coefficient of proportionality equal to 1.

The design of the key illustrated by drawings (figure 3 and figure 4). Figure 3 shows the principle design of the proposed technical solutions. Figure 4 is a comparative graph of the output characteristics, where 1 is the dependence of Q/QMr.=f(p/pMr.), 2 - dependence of the N/NMr.=f(p/pMr.).

Universal hydraulic suspension pipe wrench consists of a power unit 1, the actuator 2, the measuring devices 3, the hydraulic circuit according to the respective valves 4.

The power unit includes a motor 5, a sleeve 6, a pump 7, a tank with a working medium 8, the constant power regulator 9. The actuator includes a hydraulic motor 10, the transmission 11, the satellites 12 disclosed rotating the rotor 13, the clamping unit mounted pipe 14, a housing 15, the movable sash 16, the lock 17, the valve 18, the valve 19. The constant power regulator consists of a piston 20, a pre-compressed spring 21, the stop 22, the spring 23 and the cylindrical block 24, the connecting pipe 25.

As the hydraulic pump 7 can be used to pump axial piston type with sloping arrangement of the pistons. (Basta T.M. Calculations and designs of airplane hydraulic devices. M: the State scientific and technical publishing house barongis, 1961). The advantage of these pumps is the ability to change their performance by changing the angle of inclination of the pistons relative to the longitudinal axis of the drive motor (angle α).

The hydraulic motor 10 is a hydraulic machines axial piston type. Transmission 11, satellites 12 disclosed rotating the rotor 13 converts rotary motion device of the grip tube 14. The ratio of the speeds of rotation of the shaft of the motor 10 and the pipe clamp 14 is selected on the basis of securing the range is rebbekah values twisting (otbrosivshego) point mounted on the pipe.

The drive motor provides constant speed of rotation of the output shaft independently of the load to ensure the operation of the power unit can be taken that the motor speed 5 constant).

The hydraulic distributor 18 allows you to change the direction of rotation of the motor 10 and to operate in manual mode performance, it usually is used at the initial stage of screwing (unscrewing) of the pipe to ensure the correct entry of the threaded connection. The consumption of the working fluid in the power unit remains unchanged, as part of the working fluid from the valve 18 is discharged into the tank 8.

In normal mode the proposed universal hydraulic suspension key works in the following way. Working fluid from the tank 8 through line enters the hydraulic pump 7 and after discharge up to a certain pressure depending on the hydraulic resistance of the system, enters the valve 18 and the constant power regulator 9. Depending on the handle position of the control valve 18 of the hydraulic motor 10 can rotate in either direction or to remain stationary. In the case of a rotation shaft of the motor 10, the device gearing mounted pipe 14 also starts to rotate. With the help of special equipment carried is raised sure grip mounted pipe and in the future is their synchronous rotation.

The constant power regulator 9 in the General case may have a different device, in this case it is intended for correcting the output characteristics of the key depending on certain external factors.

The constant power regulator 9 operates as follows. Working fluid is supplied into the cylinder chamber 24. However, the piston 20 remains in place, as the spring 21 is hindered. The capacity of the hydraulic pump 7 (power of the motor 5) will proportionally increase with the increase in external load, and the performance remains unchanged, since the actuator (clutch 6 and the motor 5) rotates at a constant speed.

Upon reaching the output power of the motor nominal values of the piston 20 overcomes the force of the spring 21 and begins to move. The stop 22 is pressed on the cylindrical cradle motion unit of the hydraulic pump 7, resulting angle α reduced, however, the performance varies inversely proportional to the external load. Since the spring 23 also provides resistance to movement of the piston 20, the output characteristics are adjusted by means of two springs, namely the spring 21 and the spring 23. As the spring 21 is pre-compressed and the function of the delay device, by adjusting the degree of compression can be achieved, a complete matching of real output feature is the properties required for the optimal operation of the power unit and key in General. A regulating factor of the device for correcting output characteristics of the selected hydraulic pressure of the working fluid as it depends almost linearly on the moment resistance of the assembled tube. This greatly simplifies the design of the power unit 1, and the constant power regulator, which is a device for correcting the output characteristics, can be mounted inside the hydraulic pump 7.

The relief valve 19 serves to disable the motor 10 in case of exceeding the hydraulic pressure in the system above is valid.

The hydraulic circuits with respective valves 4 are for the formation of the hydraulic circuits. Measuring devices 3 are needed to control the operation of the key. These include pressure gauges, gauges, torque etc.

The design of the key allows you to increase the coefficient of versatility through the use of hydraulic pump axial piston type with a device for correcting the output characteristics in the form of the constant power regulator. The upper boundary of the range of changes in mass overall characteristics of the assembled pipe is only limited by the pressure of the working fluid in the supply lines of the key, and not the capacity of the hydraulic pump (drive)that took place in the prototype. Ceteris paribus, this boundary can be the modified upwards by adjusting a gear ratio of the mechanical chain: the shaft of the motor - gearbox - satellites - ring rotor - device for clamping the assembled tubes. The range of changes in nomenclature mounted pipes can also be extended by using a more powerful pump and actuator. Therefore, the proposed construction of the pipe wrench is compared with the prototype greater coefficient of versatility.

Improving the efficiency of the key is achieved by the fact that the output characteristics are optimized by dividing the operation mode of the power unit on two characteristic sites, with the first segment with increasing load increases in proportion to the output power of the power unit, and its performance remains unchanged, the second part of the output power remains constant, and the performance decreases inversely proportional to the load (figure 4). As noted above, to obtain a similar output characteristics allows the use of a corrective device. In this case, the actuator operates primarily in the nominal mode, therefore, has a maximum efficiency.

As can be seen from figure 4, the output characteristics are not areas with abrupt change their values, so the moving parts of the actuator are not experiencing shock loadings, and EIT is it the degree of wear is significantly less in comparison with the degree of wear of the actuator prototype.

Thus, the application of universal hydraulic suspension key allows you to increase efficiency, to reduce the degree of wear of the moving parts of the actuator, as well as to increase the ratio of the universality of the key.

Universal hydraulic suspension pipe wrench, comprising a power unit containing a drive motor connected therewith by coupling the hydraulic pump with a device for the correction performance of the hydraulic pump and the output power of the power unit and tank with a working body, formed by the layout of its elements in a single housing, the actuator including a hydraulic motor, gearbox, disclosed a rotating rotor with a pipe clamp and a movable sash lock, valve, safety valves, measuring devices, the respective hydraulic circuits with the main hydrological and necessary valves, characterized in that the device for the correction performance of the hydraulic pump and the output power of the power the unit is made in the form of the constant power regulator with delay device, for example, in the form of pre-compressed springs, the quality is as hydraulic pump used pump axial piston type with a cylindrical movable block, includes spring, and with the inclined position of the piston, providing the ability to change the performance of the pump by changing the angle of inclination of the pistons relative to the longitudinal axis of the drive motor, and the entrance to the constant power regulator connected to the main hydrological, and the output from the cylindrical movable block of the hydraulic pump and the constant power regulator configured to include a delay device, for example, in the form of a pre-compressed spring, when reaching the output power of the power unit and the performance of the pump, determining the mode of operation of key values specified by the formula

where N, NMr.- accordingly, the output power nominal output power of the power unit;

Q, QMr.accordingly, the productivity, the nominal capacity of the hydraulic pump;

R, RMr.- pressure, nominal pressure working fluid in the supply lines, P≥PMr.;

k - coefficient of proportionality equal to 1.



 

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EFFECT: enhanced efficiency, reduced wear; increased universality factor.

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